Limit flickr JSON image number?

I tried this URL and it works fine...

http://api.flickr.com/serv开发者_开发知识库ices/feeds/photos_public.gne?per_page=6&jsoncallback=?

...almost. It is set to "per_page=6" but it don't listen to it. What's wrong?

You have an extra question mark at the end. Can you remove the last parameter?

It seems like this URL does not accept any limit.

Unfortunately according to the API this isn't supported

http://www.flickr.com/services/feeds/docs/groups_pool/

I was in need of it as well